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Summary
DescriptionAshContours.png
English: Contour lines, cm scale, showing accumulation of ash from 3 episodes of Plinian pumice falls over 60 hours during the 1912 Novarupta eruption
Date
Source
The Novarupta-Katmai eruption of 1912—largest eruption of the twentieth
century; centennial perspectives: U.S. Geological Survey Professional Paper 1791
Author
Hildreth, W., and Fierstein, J.
Licensing
Public domainPublic domainfalsefalse
This work is in the public domain in the United States because it is a work prepared by an officer or employee of the United States Government as part of that person’s official duties under the terms of Title 17, Chapter 1, Section 105 of the US Code.
Note: This only applies to original works of the Federal Government and not to the work of any individual U.S. state, territory, commonwealth, county, municipality, or any other subdivision. This template also does not apply to postage stamp designs published by the United States Postal Service since 1978. (See § 313.6(C)(1) of Compendium of U.S. Copyright Office Practices). It also does not apply to certain US coins; see The US Mint Terms of Use.
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.
https://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse
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20 January 2001
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image/png
checksum
d194714697be5e7ad26de38bfc3021b251ef5798
determination method: SHA-1
data size
174,293 byte
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740 pixel
width
605 pixel
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20:39, 2 August 2018
605 × 740 (170 KB)
Pi3.124
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